Unlicensed use of the broadcast television spectrum by unlicensed communications devices (UCDs) on a non-interfering basis may be possible in various jurisdictions, since some of the video and data signals transmitted by UCDs may be formatted according to existing digital television standards. However, such ad hoc video and data signal transmissions from UCDs may be difficult to distinguish from each other, and/or from licensed (e.g., commercial) broadcasts. For more information regarding digital television standards, please see “ATSC Standard A/53 (1995): ATSC Digital Television Standard,” Advanced Television Systems Committee, Washington, D.C., 1994, and amendments thereto.